AP Photo/Sue OgrockiRussell Westbrook scored a team-high 29 points as the Thunder took a 2-0 series lead over the Mavs.

Physical play has dominated the discussion about this series pitting teams separated by a couple hundred miles. Coaches Rick Carlisle and Scott Brooks, former Continental Basketball Association roommates, went back and forth via the media between games about whether the Thunder were getting away with grabbing and holding Dirk Nowitzki too often and if Carlisle was publicly campaigning for more calls.

That was just the beginning of the fun. Things really got heated during the Thunder's 102-99 Game 2 victory Monday night, which gave Oklahoma City a 2-0 lead as the series heads south on Interstate 35.

If you want to pinpoint the moment this officially became a rivalry, it was when Oklahoma City enforcer Kendrick Perkins thrust his forearm in Nowitzki's back with great force midway through the first quarter.

In an apparent attempt to intimidate, Perkins approached Nowitzki after being whistled for a loose ball foul. Nowitzki made it clear he wasn't going to back down, slamming his right shoulder into Perkins, who responded by shoving Nowitzki with his right hand.

Then, they shouted at each other several words that aren't appropriate for national television, not even a late-night audience, as players and officials separated Perkins and Nowitzki.

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Speaking of which, censors didn't catch the expletive Carlisle dropped while discussing the incident during his live-televised postgame news conference.

"The dirty bulls--- has got to stop," Carlisle said.

Doesn't that just give you warm, fuzzy feelings?

The teams traded figurative haymakers in the first half after the Perk-Dirk brouhaha -- a 19-3 run by the Thunder and a 17-4 spurt by the Mavs -- to set up a back-and-forth second half and another down-to-the-wire finish in what has been by far the most entertaining first-round series.

The OKC kids -- who got schooled in crunch time by the savvy, veteran Mavs last season -- closed again. But the old Mavs made it clear that it's going to take much more than a few punches to knock out the defending champions.

"We're not going to give it to them," Nowitzki said after scoring a game-high 31 points in a losing effort. "They're going to have to take it."

Said Perkins: "I mean, it's just grown men out here playing basketball and teams trying to advance. You know, you're just out here playing. There's nothing to hurt nobody or nothing like that. Neither side is going to bow down. They're not, we're not, so we're just out here playing and competing on a high level."

This series features two of the NBA's most gentlemanly superstars in Nowitzki and Kevin Durant, but there is not a lot of love lost between the Mavs and Thunder right now, particularly from the down-two-games defending champs.

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Dallas defensive stopper Shawn Marion is miffed that Durant got so much glory for the "tough-ass shot, lucky bounce" that won Game 1. The Matrix is mad that Durant, who is averaging 25.5 points in the series despite shooting 34.1 percent from the floor, is getting so many whistles in his favor.

Nowitzki has minded his manners when talking to the media, but he's obviously annoyed by the hands-on (and elbow-on and forearms-on) defense being played by Perkins and Serge Ibaka. Nowitzki shouted at Ibaka after the Thunder's shot-blocker supreme slapped Nowitzki in the face while following through after trying to swat a jumper, just moments before squaring up with Perkins.

And the Mavs are really mad that they've been in position to win both games but couldn't get the job done against a team whose four best players are younger than baby-faced Dallas benchwarmer Rodrigue Beaubois.

"Games like these in the playoffs are going to get chippy," Durant said.

The fun has just begun. Let the hard feelings and hard fouls continue. That's how it rolls in a rivalry.